4 files changed, 178 insertions, 0 deletions
diff --git a/tests/language-feature/interfaces/default-method-differentiable.slang b/tests/language-feature/interfaces/default-method-differentiable.slang
new file mode 100644
index 000000000..4cd5dc1ed
--- /dev/null
+++ b/tests/language-feature/interfaces/default-method-differentiable.slang
@@ -0,0 +1,42 @@
+//TEST(compute):COMPARE_COMPUTE(filecheck-buffer=CHECK): -shaderobj -output-using-type
+
+// Test that a default interface method can be differentiable.
+
+interface IFoo<int v>
+{
+    [Differentiable]
+    float getVal(float x);
+
+    [Differentiable]
+    float getGreaterVal<int y>(float x)
+    {
+        return getVal(x) + y + v;
+    }
+}
+
+struct Impl : IFoo<2>
+{
+    [Differentiable]
+    float getVal(float x)
+    {
+        return x*x;
+    }
+    
+    // Using the default implementation for getGreaterVal.
+}
+
+[Differentiable]
+float test<int y, T:IFoo<y>>(T v, float x) { return v.getGreaterVal<1>(x); }
+
+//TEST_INPUT: set resultBuffer = out ubuffer(data=[0 0 0 0], stride=4)
+RWStructuredBuffer<float> resultBuffer;
+
+[numthreads(1,1,1)]
+void computeMain()
+{
+    Impl impl = {};
+    var dpx = diffPair(3.0);
+    bwd_diff(test)(impl, dpx, 1.0f);
+    resultBuffer[0] = dpx.d;
+    // CHECK: 6.0
+}
diff --git a/tests/language-feature/interfaces/default-method-generic-interface.slang b/tests/language-feature/interfaces/default-method-generic-interface.slang
new file mode 100644
index 000000000..fb32b2001
--- /dev/null
+++ b/tests/language-feature/interfaces/default-method-generic-interface.slang
@@ -0,0 +1,55 @@
+//TEST(compute):COMPARE_COMPUTE(filecheck-buffer=CHECK): -shaderobj -output-using-type
+
+// Test that a generic interface method in a generic interface
+// can have a body providing default implementation.
+
+interface IFoo<int v>
+{
+    int getVal();
+    int getGreaterVal<int x>()
+    {
+        return getVal() + x + v;
+    }
+}
+
+struct Impl : IFoo<2>
+{
+    int getVal()
+    {
+        return 42;
+    }
+    
+    // Using the default implementation for getGreaterVal.
+}
+
+struct Impl2 : IFoo<2>
+{
+    int getVal()
+    {
+        return 42;
+    }
+    
+    // overriding default implementation.
+    int getGreaterVal<int x>()
+    {
+        return 100 + x;
+    }
+}
+
+int test<int y, T:IFoo<y>>(T v) { return v.getGreaterVal<1>(); }
+
+//TEST_INPUT: set resultBuffer = out ubuffer(data=[0 0 0 0], stride=4)
+RWStructuredBuffer<int> resultBuffer;
+
+[numthreads(1,1,1)]
+void computeMain()
+{
+    Impl impl = {};
+    int result = test(impl);
+    resultBuffer[0] = result;
+    // CHECK: 45
+
+    Impl2 impl2 = {};
+    resultBuffer[1] = test(impl2);
+    // CHECK: 101
+}
+\ No newline at end of file
diff --git a/tests/language-feature/interfaces/default-method-generic.slang b/tests/language-feature/interfaces/default-method-generic.slang
new file mode 100644
index 000000000..48e1d98de
--- /dev/null
+++ b/tests/language-feature/interfaces/default-method-generic.slang
@@ -0,0 +1,36 @@
+//TEST(compute):COMPARE_COMPUTE(filecheck-buffer=CHECK): -shaderobj -output-using-type
+
+// Test that a generic interface method can have a body providing default implementation.
+
+interface IFoo
+{
+    int getVal();
+    int getGreaterVal<int x>()
+    {
+        return getVal() + x;
+    }
+}
+
+struct Impl : IFoo
+{
+    int getVal()
+    {
+        return 42;
+    }
+    
+    // Using the default implementation for getGreaterVal.
+}
+
+int test<T:IFoo>(T v) { return v.getGreaterVal<1>(); }
+
+//TEST_INPUT: set resultBuffer = out ubuffer(data=[0 0 0 0], stride=4)
+RWStructuredBuffer<int> resultBuffer;
+
+[numthreads(1,1,1)]
+void computeMain()
+{
+    Impl impl = {};
+    int result = test(impl);
+    resultBuffer[0] = result;
+    // CHECK: 43
+}
+\ No newline at end of file
diff --git a/tests/language-feature/interfaces/default-method.slang b/tests/language-feature/interfaces/default-method.slang
new file mode 100644
index 000000000..98bebc1e3
--- /dev/null
+++ b/tests/language-feature/interfaces/default-method.slang
@@ -0,0 +1,45 @@
+//TEST(compute):COMPARE_COMPUTE(filecheck-buffer=CHECK): -shaderobj -output-using-type
+
+// Test that interface method can have a body providing default implementation.
+
+interface IFoo
+{
+    int getVal();
+    int getGreaterVal()
+    {
+        return getVal() + 1;
+    }
+    static int getStaticVal()
+    {
+        return 100;
+    }
+}
+
+struct Impl : IFoo
+{
+    int getVal()
+    {
+        return 42;
+    }
+    
+    // Using the default implementation for getGreaterVal.
+}
+
+int test<T:IFoo>(T v) { return v.getGreaterVal(); }
+
+int test2<T:IFoo>() { return T.getStaticVal();}
+
+//TEST_INPUT: set resultBuffer = out ubuffer(data=[0 0 0 0], stride=4)
+RWStructuredBuffer<int> resultBuffer;
+
+[numthreads(1,1,1)]
+void computeMain()
+{
+    Impl impl = {};
+    int result = test(impl);
+    resultBuffer[0] = result;
+    // CHECK: 43
+
+    resultBuffer[1] = test2<Impl>();
+    // CHECK: 100
+}
+\ No newline at end of file